Several MSNBC employees, who spoke about programming plans on the condition of anonymity, said the most likely candidate for a new show was the Washington Post columnist Ezra Klein, a frequent substitute for Ms. Maddow. Mr. Klein may start with a weekend time slot, but these people said the 8 p.m. weekday time slot held by Mr. Schultz was also a possibility.

Schultz, who has hosted "The Ed Show" since 2009 on the network, now anchors MSNBC's 8 p.m. weeknight slot. Klein often guest hosts "The Rachel Maddow Show" during the 9 p.m. hour.